<!DOCTYPE html>
<html lang="en-US">
  <head>
    <link href="/assets/index.css" rel="stylesheet" type="text/css" />
    <script crossorigin="anonymous" src="https://unpkg.com/@babel/standalone@7.8.7/babel.min.js"></script>
    <script crossorigin="anonymous" src="https://unpkg.com/react@16.8.6/umd/react.development.js"></script>
    <script crossorigin="anonymous" src="https://unpkg.com/react-dom@16.8.6/umd/react-dom.development.js"></script>
    <script crossorigin="anonymous" src="/test-harness.js"></script>
    <script crossorigin="anonymous" src="/test-page-object.js"></script>
    <script crossorigin="anonymous" src="/__dist__/webchat-es5.js"></script>
  </head>
  <body>
    <main id="webchat"></main>
    <script type="text/babel" data-presets="env,stage-3,react">
      const {
        WebChat: {
          Components: { BasicWebChat, Composer },
          hooks: { useScrollDown, useScrollUp }
        }
      } = window;

      run(async function () {
        const res = await fetch('/assets/transcripts/markdown-message.json');

        if (!res.ok) {
          throw new Error(`Server returned ${res.status} while fetching transcript`);
        }

        const directLine = testHelpers.createDirectLineWithTranscript(await res.json());
        const store = testHelpers.createStore();

        const RunFunction = ({ fn }) => {
          fn();

          return false;
        };

        const renderWithFunction = fn =>
          new Promise(resolve =>
            ReactDOM.render(
              <Composer directLine={directLine} store={store}>
                <BasicWebChat />
                <RunFunction fn={() => resolve(fn && fn())} key={Date.now() + ''} />
              </Composer>,
              document.getElementById('webchat')
            )
          );

        await renderWithFunction();

        await pageConditions.uiConnected();
        await pageConditions.scrollStabilized();

        const scrollable = pageElements.transcriptScrollable();
        const scrollTopAtBottommost = scrollable.scrollHeight - scrollable.offsetHeight;

        expect(scrollable.scrollTop).toBe(scrollTopAtBottommost);

        // Call useScrollUp() should scroll the transcript view up
        await renderWithFunction(() => Promise.resolve(useScrollUp()).then(fn => fn()));
        await pageConditions.scrollStabilized();
        expect(scrollable.scrollTop).toBeLessThan(scrollTopAtBottommost);

        // Call useScrollDown() should scroll the transcript view down, back at the bottommost position
        await renderWithFunction(() => Promise.resolve(useScrollDown()).then(fn => fn()));
        await pageConditions.scrollStabilized();
        expect(scrollable.scrollTop).toBe(scrollTopAtBottommost);
      });
    </script>
  </body>
</html>
